46 Rev. T. Hincks on new British Hydroids. 



The polypes, with their numerous tentacles, of moderate 

 length, surrounding a large and expanded oral disk, bear some 

 resemblance to a full-blown flower. When withdrawn, the arms 

 bend inwards. 



The gonophores, which are produced on the creeping stolon 

 (fig. 4 e), rise, as the polypes do, from within a cup-like extension 

 of the polypary. They are supported on a peduncle of some 

 length, and, when fully developed, exceed the polypes consider- 

 ably in size. I have not succeeded in making out all the details 

 of the structure, nor in tracing the whole course of development. 

 The sac which immediately contains the ova is enclosed in a 

 more or less transparent envelope, which, at a certain stage, 

 exhibits at the summit the appearance of a ribbed covering or 

 lid. I conjecture that this lid is cast off, and that the outer 

 envelope sloughs away, leaving the inner sac free for the 

 discharge of the generative products. From the base of the 

 sporosac proceed four much-branched vessels, terminating near 

 the top of it in blind extremities, and immediately enclosing the 

 ova, which fill with a dense mass the interior of the cavity. I 

 have counted about 300, which had been pressed out of a single 

 gonophore. The ovum consists of a cream-coloured granular 

 substance, the germinal vesicle showing as a depression, and the 

 spot as a circle with a raised rim. 



I could detect no trace of a manubrium, nor did I witness the 

 liberation of the reproductive elements. 



The outer envelope of the gonophore is filled with the long 

 bean-shaped thread-cells, which are also present in amazing 

 numbers in the ectoderm of the ccenosarc. 



All the known members of the genus Atractylis are propa- 

 gated by means of free gonozooids, with the exception oi A. are- 

 nosa and the present species. 



I'am. Campanulariadae. 



Genus Laomedea, Lamouroux. 



L.fragilis, n. sp. PI. IX. fig. 3. 



Polypary very minute and delicate. Stem flexuose, giving off 

 a branch at every flexure, which is annulated and tapers up- 

 wards, terminating in a much elongated and very narrow cell, 

 with an even rim. The stem exhibits three or four rings (often 

 very indistinct) above the origin of each branch. 



Height about i inch. 



Habitat. In pools on the lower ledges of the Capstone, Ilfra- 

 combe, forming miniature groves on the under side of stones. 



This species is smaller and more delicate in habit even than 



